Menu: Solids / Solid Define
Shortcut Key: Ctrl+D
Combines all the currently selected entities as a single solid. This allows you to build solids from a collection of planes, extrusions, and surfaces.
A Solid must be a closed set of planes and surfaces. This command does not verify whether the current selection is a legitimate Solid. If you define an invalid Solid, operations such as Solid Add or Solid Subtract command may not work correctly.